Bell curve shape to crystal quality may point to best candidates for flight
Sept. 20, 1999: Did you ever ask the teacher to grade a tough test "on the curve"? What you were asking was that the grades be adjusted so that a "C" fell under the part of the curve where most of your classmates had scored. A few were to the left and got a D or F; and few were to the right and got a B or an A.
That's basically how the bell curve works. In nature, objects and events quite often can be grouped along a bell curve. In a population of adult animals, most will be around the same size. A few will be larger and a few will be smaller.
"If you talk to statisticians," noted Dr. Russell Judge of the University of Alabama in Huntsville, "variations within populations in nature can be described in terms of distributions."
Judge is not a statistician but a chemical engineer who has found that protein crystals may follow much the same pattern as they form. In the current issue of Biophysical Journal, Judge, working at NASA's Marshall Space Flight Center with other researchers from UAH, NASA/Marshall, and Michigan State University at East Lansing, report that even under ideal conditions, crystals exhibit a variation in crystal quality.
The question now is whether scientists can use the microgravity of space to shift the curve to the right to grow the large, nearly perfect crystals they need for molecular lock-picking, the first step in designing drugs that can treat a broad range of diseases and disorders.
"We want to determine how the growth of crystals effect their quality," Judge
said in May when NASA selected his investigation for development, "and then take
that into space to see how microgravity is enhancing the growth characteristics
that lead to good crystals. From this we want to develop techniques, so that by
observing crystal growth on the ground, we can predict which proteins are likely
to benefit the most from microgravity crystallizat
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Contact: John Horack
john.horack@msfc.nasa.gov
256-544-1872
NASA/Marshall Space Flight Center--Space Sciences Laboratory
20-Sep-1999